New Frontiers in Old Areas--Wyoming

J. D. Love, Ann Coe Christiansen

The first producing oil well in Wyoming was drilled in 1883 on Dallas dome in the central part of the state; in 1983 it was still capable of production. The first geologic map of Wyoming, published by W. C. Knight in 1900, showed 14 oil fields and oil seeps. The next map, "Map of the Wyoming Oil Fields," was published anonymously in 1917 and showed 62 oil fields, some of which were imaginary and others, such as Lost Cabin, that were "found" and first produced 40 years after the map was published.

Oil and gas field overprints on the geologic maps of Wyoming in 1925, 1955, and 1985 showed about 41, 155, and 780 oil fields and 30, 88, and 400 gas fields. In the thrust belt of western Wyoming, more than 25 oil and gas fields have been discovered since 1975. Five rank as "giant" oil (100 million bbl) or gas (1 tcf) fields. Two fields, Whitney Canyon-Carter Creek and Riley Ridge, may be among the ten largest oil and gas fields in the world as of 1985.

The large number of oil and gas fields discovered, in part because of stratigraphic plays, between 1955 and 1985 in the Green River and Powder River basins suggests that additional fields will be found in these basins and in other Wyoming basins as drilling continues. Production, mostly from depths of less than 10,000 ft, will increase as drilling techniques become more sophisticated. Oil and gas also may be obtained in the future from within, as well as from under, volcanic rocks in northwestern Wyoming and from under the basin-margin thrust faults.

AAPG Search and Discovery Article #91043©1986 AAPG Annual Convention, Atlanta, Georgia, June 15-18, 1986.